Wow, bit of a topic here!! i had non drinking parents (well they prob had the odd wine, I didn't notice really) but now have an alcoholic brother and sister, and I was a binge drinker. I don't think giving alcohol early prevents wanting it later on, I think if it is given early and the "child" likes it, they will continue to drink, home and elsewhere.
I will never be offering my underage kids drinks. I don't mind a sip of wine once every now and then WHEN 15 or so, but never more than a sip (just because what child doesn't ask for a sip). I also believe adults have a right to drink and be able to say " I can have this, you can't", do we want them growing up totally sheltered. There are just some things kids can't do that adults can. We don't not drive because our kids aren't allowed. I grew up with a smoking grandmother and aunt and not ONCE did anyone comment on it, it was so not a big deal that I never was curious about it, and neither were my cousins (out of 13 of them, 8 with smoking parents, only 2 smoke). I think it was much better when I was younger, these days the emphasis on not drinking or smoking really adds to a childs curiousity IMO.
Guess we all differ on this one, and I guess it comes down to doing what you think is best. And like most things in life, if the child has a healthy self esteem, that's the best thing (now how do I get one of those for my girls)!!! xo